FileDocCategorySizeDatePackage
File.javaAPI DocApache Lucene 1.97803Mon Feb 20 09:18:00 GMT 2006org.apache.lucene.store.db

File

public class File extends Object
author
Andi Vajda

Fields Summary
protected static Random
random
protected com.sleepycat.db.DatabaseEntry
key
protected com.sleepycat.db.DatabaseEntry
data
protected long
length
protected long
timeModified
protected String
name
protected byte[]
uuid
Constructors Summary
protected File(String name)


      
         
    
        setName(name);

        data = new DatabaseEntry(new byte[32]);
        data.setUserBuffer(data.getSize(), true);
    
protected File(DbDirectory directory, String name, boolean create)

        this(name);

        if (!exists(directory))
        {
            if (!create)
                throw new IOException("File does not exist: " + name);
            else
            {
                DatabaseEntry key = new DatabaseEntry(new byte[24]);
                DatabaseEntry data = new DatabaseEntry(null);
                Db blocks = directory.blocks;
                DbTxn txn = directory.txn;
                int flags = directory.flags;

                key.setUserBuffer(24, true);
                data.setPartial(true);

                uuid = new byte[16];

                try {
                    do {
                        /* generate a v.4 random-uuid unique to this db */
                        random.nextBytes(uuid);
                        uuid[6] = (byte) ((byte) 0x40 |
                                          (uuid[6] & (byte) 0x0f));
                        uuid[8] = (byte) ((byte) 0x80 |
                                          (uuid[8] & (byte) 0x3f));
                        System.arraycopy(uuid, 0, key.getData(), 0, 16);
                    } while (blocks.get(txn, key, data,
                                        flags) != DbConstants.DB_NOTFOUND);
                } catch (DatabaseException e) {
                    throw new IOException(e.getMessage());
                }
            }
        }
        else if (create)
            length = 0L;
    
Methods Summary
protected voiddelete(DbDirectory directory)

        if (!exists(directory))
            throw new IOException("File does not exist: " + getName());

        Dbc cursor = null;

        try {
            try {
                byte[] bytes = getKey();
                int ulen = bytes.length + 8;
                byte[] cursorBytes = new byte[ulen];
                DatabaseEntry cursorKey = new DatabaseEntry(cursorBytes);
                DatabaseEntry cursorData = new DatabaseEntry(null);
                Db files = directory.files;
                Db blocks = directory.blocks;
                DbTxn txn = directory.txn;
                int flags = directory.flags;

                System.arraycopy(bytes, 0, cursorBytes, 0, bytes.length);
                cursorKey.setUserBuffer(ulen, true);
                cursorData.setPartial(true);

                cursor = blocks.cursor(txn, flags);

                if (cursor.get(cursorKey, cursorData,
                               DbConstants.DB_SET_RANGE | flags) != DbConstants.DB_NOTFOUND)
                {
                    cursor.del(0);

                    while (cursor.get(cursorKey, cursorData,
                                      DbConstants.DB_NEXT | flags) != DbConstants.DB_NOTFOUND) {
                        for (int i = 0; i < bytes.length; i++)
                            if (bytes[i] != cursorBytes[i])
                                return;

                        cursor.del(0);
                    }
                }

                files.del(txn, key, 0);
            } finally {
                if (cursor != null)
                    cursor.close();
            }
        } catch (DatabaseException e) {
            throw new IOException(e.getMessage());
        }
    
protected booleanexists(DbDirectory directory)

        Db files = directory.files;
        DbTxn txn = directory.txn;
        int flags = directory.flags;

        try {
            if (files.get(txn, key, data, flags) == DbConstants.DB_NOTFOUND)
                return false;
        } catch (DatabaseException e) {
            throw new IOException(e.getMessage());
        }
        
        byte[] bytes = data.getData();
        ByteArrayInputStream buffer = new ByteArrayInputStream(bytes);
        DataInputStream in = new DataInputStream(buffer);

        length = in.readLong();
        timeModified = in.readLong();
        in.close();

        uuid = new byte[16];
        System.arraycopy(bytes, 16, uuid, 0, 16);

        return true;
    
protected byte[]getKey()

        if (uuid == null)
            throw new IOException("Uninitialized file");

        return uuid;
    
protected longgetLength()

        return length;
    
protected java.lang.StringgetName()

        return name;
    
protected longgetTimeModified()

        return timeModified;
    
protected voidmodify(DbDirectory directory, long length, long timeModified)

        ByteArrayOutputStream buffer = new ByteArrayOutputStream(32);
        DataOutputStream out = new DataOutputStream(buffer);
        Db files = directory.files;
        DbTxn txn = directory.txn;

        out.writeLong(length);
        out.writeLong(timeModified);
        out.write(getKey());
        out.close();

        System.arraycopy(buffer.toByteArray(), 0, data.getData(), 0, 32);

        try {
            files.put(txn, key, data, 0);
        } catch (DatabaseException e) {
            throw new IOException(e.getMessage());
        }
        
        this.length = length;
        this.timeModified = timeModified;
    
protected voidrename(DbDirectory directory, java.lang.String name)

        if (!exists(directory))
            throw new IOException("File does not exist: " + getName());

        File newFile = new File(name);

        if (newFile.exists(directory))
            newFile.delete(directory);

        try {
            Db files = directory.files;
            DbTxn txn = directory.txn;

            files.del(txn, key, 0);
            setName(name);
            files.put(txn, key, data, 0);
        } catch (DatabaseException e) {
            throw new IOException(e.getMessage());
        }
    
private voidsetName(java.lang.String name)

        ByteArrayOutputStream buffer = new ByteArrayOutputStream(128);
        DataOutputStream out = new DataOutputStream(buffer);

        out.writeUTF(name);
        out.close();

        key = new DatabaseEntry(buffer.toByteArray());
        key.setUserBuffer(key.getSize(), true);

        this.name = name;